Main advantages of dual battery charger in mobile are:

The dual battery mobile charging unit in mobile phones is very useful for the customers to continue using mobile phones when the main battery goes down due to low battery.

Avoiding uninterrupted power supply from the battery will ensure customers to keep using mobile phone.

No need to carry the mobile charging device while travelling

Pen drive is very light weight, easy to carry in pocket and also to operate

Low cost device and it can be charged easily by fixing it onto a computer.